An editorial and letter, published simultaneously by the BMJ and Lancet today, warn that failure to agree radical cuts in carbon dioxide emissions at the UN climate change conference in Copenhagen this December spells a global health catastrophe.
The scientific evidence that global temperatures are rising and that man is responsible has been widely accepted since the Intergovernmental Panel on Climate Change's report in 2007, write Lord Michael Jay and Professor Michael Marmot in the editorial. There is now equally wide consensus that we need to act now to prevent irreversible climate change.
So the chances of success should be good but the politics are tough, they say.
The most vocal arguments are about equity: the rich world caused the problem so why should the poor world pay to put it right? Can the rich world do enough through its own actions and through its financial and technological support for the poor to persuade the poor to join in a global agreement?
These arguments need to be tackled head on, but Jay and Marmot believe that what's good for the climate is good for health. For example, a low carbon economy will mean less pollution. A low carbon diet (especially eating less meat) and more exercise will mean less cancer, obesity, diabetes, and heart disease. This is an opportunity too to advance health equity, which is increasingly seen as necessary for a healthy and happy society, they say.
They point out that the threat to health is especially evident in poorest countries, particularly in sub-Saharan Africa, where poverty and lack of resources, infrastructure, and often governance, greatly increase their vulnerability to the effects of climate change.
If we take climate change seriously, it will require major changes to the way we live, reducing the gap between carbon rich and carbon poor within and between countries, they write.
A successful outcome at Copenhagen is vital for our future as a species and for our civilisation. Failure to agree radical reductions in emissions spells a global health catastrophe, which is why health professionals must put their case forcefully now and after Copenhagen, they conclude.
In the accompanying letter, doctors leaders across the world call on politicians to heed the health effects of climate change when they meet in Copenhagen.
They warn that "there is a real danger that politicians will be indecisive, especially in such turbulent economic times as these."
Doctors are still seen as respected and independent, largely trusted by their patients and the societies in which they practise, they write. As such, they urge doctors "to demand that their politicians listen to the clear facts that have been identified in relation to climate change and act now to implement strategies that will benefit health of communities worldwide."
"Politicians may be scared to push for radical reductions in emissions because some of the necessary changes to the way we live won't please voters," said Dr Fiona Godlee, editor in chief of the BMJ. "Doctors are under no such constraint. On the contrary we have a responsibility as health professionals to warn people how bad things are likely to get if we don't act now. The good news is that we have a positive message - that what is good for the climate is good for health."